This invention relates to pressurized spray paint containers, and in particular to a new and improved process and apparatus for handling such containers.
A typical pressurized spray paint container is shown in FIG. 1 and comprises a cylindrical can 21 with a top 22 and a bottom 23. A spray control nozzle 24 is mounted in the top 22, and a transport tube 25 is positioned within the container. The outlet end of the transport tube is connected to the control nozzle and the inlet end of the tube terminates adjacent the bottom 23. The container is charged with a mixture of paint solids 27, paint solvent 28, and a propellant 29.
In use, the container is shaken to mix the paint solids and paint solvent and then the spray control nozzle is manually depressed, with the container in a generally upright position. Depressing the nozzle opens a flow path from the interior of the container up through the transport tube and out the spray nozzle, with the propellant forcing the paint solvent/solid mixture out the nozzle.
During storage, the paint solids settle at the bottom of the container, as shown in FIG. 1. Sometimes a metal ball 30 is included within the container to aid in mixing the paint solids and solvent when the container is shaken.
Pressurized spray paint containers of the type described above have been generally available and widely used for many years. However there is a problem with this product, which problem has been in existence since the pressurized spray paint container was first available, and which problem has not been satisfactorily resolved. When a container is stored for any period of time, the paint solids settle to the bottom, as shown in FIG. 1, and some of the solids enter the inlet end of the transport tube, particularly after the container has been used for some painting operation. Once the paint solids harden in the transport tube, the container is no longer usable since it is nearly impossible to clean the hardened solids from the transport tube by agitation. This necessitates discarding the container with its still usable charge of propellant and paint.